The thesis explores a new valid multiuser detection method and a signal transmission scheme, and studies the principle of improving the spectral efficiency when multiuser detection is employed.

• 本文首先着眼于探索新的多用户检测方法或信号发送方案,然后从理论上进一步研究采用多用户检测方法时提高频谱效率的系统优化设计。